Ambush Ants: Beware the moldy patch on that branch

On the plants where they live, tiny tropical ants build fungus platforms and then hide underneath, ready to ambush insects that may be far larger than themselves.

2 BR WITH TRAP. A tropical Hirtella tree offers leaf-base pouches as ant shelters. A. Dejean and Orivel

Ants build black hideouts, above or below a branch, where they trap insects, such as this locust.